REALLY COLD outside air kit

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recppd

New Member
Hearth Supporter
Aug 30, 2006
124
North Shore, MA
I don't want to revisit a long disputed debate here, but I want to refresh my memory on whether or not it's worth having an outside fresh air kit installed on a stove. I guess I'm wondering if the extreme temperature difference negates the benefit? Please refresh my memory without bashing me to much...;)
 
If you dont't have a really new, really tight house. Forget about it.

In other words. Just about every house in the world. No matter what the builder said.
 
What does outside air do for one it will equalize pressure differencial.
plus supply a needed combustion air source.

There are two situations it is really needed, one if room combustion air vollume is lacking, or if it is located in an area where other combustion appliances are competing for the combustion air Second if you have a real tightly built home. If the internal room vollume is there, I say it is not needed.

You are correct to question it being a cold draft when the stove is not running. The air connection should be made directly to the stove's outlet and possibly with a damper closed when the stove is not in use.
Are you having combustion problems now?
 
Everything i have read about them says there more of a better idea then not.
I'm still thinking about installing one myself. If the pressurize point being true of pulling in out side air to the stove and not through leaks in the house and in turn pushing out of the leaks vs pulling sounds like a winner.

More information:
(broken link removed to http://chimneysweeponline.com/hooa.htm)
&
(broken link removed to http://chimneysweeponline.com/hooa3.htm)
 
Roospike said:
Everything i have read about them says there more of a better idean then not.
I'm still thinking about installing one myself. If the pressurize point being true of pulling in out side air to the stove and not through leaks in the house and in turn pushing out of the leaks vs pulling sounds like a winner.

More information:
(broken link removed to http://chimneysweeponline.com/hooa.htm)
&
(broken link removed to http://chimneysweeponline.com/hooa3.htm)

Check one in the pro outside air column
Good post spike
 
Alright , here is an idea i have been kicking around for a wile now.

Say your wood stove is on one side of a house ( say ranch style home ) and you run an air kit to the stove , but instead of running it from out side what about running it like under the house but connecting it to a room on the far end of the house .
With that said , now by pulling cool air from down low on one end of the house would that not force warm air from the wood stove room back to the far end of the house where the cold air is being pulled from ?
I understand that your still going to end up pulling outside air in through leaks in the home but thought this would circulate warm air.

How about some input.
 
Roo,

I don't think the amount of air the stoev combusts would be sufficient to initiate the type of convective heat movement you're thinking of. Similarly, due to frictional losses in the air intake pipe, I wouldn't suggest running any extremely long lengths of the pipe.
 
Roospike said:
Alright , here is an idea i have been kicking around for a wile now.

Say your wood stove is on one side of a house ( say ranch style home ) and you run an air kit to the stove , but instead of running it from out side what about running it like under the house but connecting it to a room on the far end of the house .
With that said , now by pulling cool air from down low on one end of the house would that not force warm air from the wood stove room back to the far end of the house where the cold air is being pulled from ?
I understand that your still going to end up pulling outside air in through leaks in the home but thought this would circulate warm air.

How about some input.

I have had that idea for about 5 years now and always wondered how it would work.

Dammit, try it!

I know you have plenty of thermometers around, and it would be easy to get a baseline before trying it.

Conceptually, it sounds great.
 
elkimmeg said:
What does outside air do for one it will equalize pressure differencial.
plus supply needed a combustion air source.

There are two situations it is really needed one if room combustion air vollume is lacking, or if it is located in an area where other combustion appliances are competing for the combustion air Second if you have a real tightly built home. If the internal room vollume is there, I say it is not needed.

You are correct to question it being a cold draft when the stove is not running. The air connection should be made directly to the stove's outlet and possibly with a damper closed when the stove is not in use.
Are you having combustion problems now?

also, correct me if Im wrong, but in a mobile home outside air is required.
 
When outside air is required Harry is correct required in mobile homes due to lack sufficient interior air volume
Outside air supplies are also required for installation of gas stoves in bedrooms. Disclaimer not all gas stoves are listed and approved for bedroom installations.
Adding an out side air supply does not make non listed one compliant. They have to be bedroom listed We are only talking about gas stoves in bedrooms not solid fuel burning appliances
 
My wood furnace is in the basement,I put a dryer vent and 4" flex pipe to the floor by the furnace. This is what manufacter recomened. They really what 6" of frash air but I did not want to cut another hole.
 
I don't think the inside air temps vs. outside air temps, that outside air temps negatively affect combustion. Whether you take 70F inside air temps and heat it to 1000 degrees, or 20F air temps and heat it to 1000F there isn't a big difference in the total picture. Plus, if I'm not mistaken the outside combustion kit is a metal tube that connects to the stove. As your stove warms up, so doesn't that metal tube the cold outside air comes in from, and that helps preheat it. How much, I don't know.
 
I guess my house is on the tight side (which it is) because when I closed the outside air kit my ears started ringing and plugging up. It was very noticable once the fire got up to temp. Opened it back up and the symptoms eventually went away. Air kit stays!
 
You will see that every application is different, and every install is unique. Glad its working for you!
 
Roospike said:
Alright , here is an idea i have been kicking around for a wile now.

Say your wood stove is on one side of a house ( say ranch style home ) and you run an air kit to the stove , but instead of running it from out side what about running it like under the house but connecting it to a room on the far end of the house .
With that said , now by pulling cool air from down low on one end of the house would that not force warm air from the wood stove room back to the far end of the house where the cold air is being pulled from ?
I understand that your still going to end up pulling outside air in through leaks in the home but thought this would circulate warm air.

How about some input.
Sounds like a good idea, but it won't work unless you cut a hole in the outside wall by the stove to complete the cycle (air return). There is no air coming out of the stove, only going in and up the chimney. If you put the air intake on the far side of the house, it will draw air from the nearest leak to the outside, not from the stove.
 
quads said:
Roospike said:
Alright , here is an idea i have been kicking around for a wile now.

Say your wood stove is on one side of a house ( say ranch style home ) and you run an air kit to the stove , but instead of running it from out side what about running it like under the house but connecting it to a room on the far end of the house .
With that said , now by pulling cool air from down low on one end of the house would that not force warm air from the wood stove room back to the far end of the house where the cold air is being pulled from ?
I understand that your still going to end up pulling outside air in through leaks in the home but thought this would circulate warm air.

How about some input.
Sounds like a good idea, but it won't work unless you cut a hole in the outside wall by the stove to complete the cycle (air return). There is no air coming out of the stove, only going in and up the chimney. If you put the air intake on the far side of the house, it will draw air from the nearest leak to the outside, not from the stove.
I think he's talking about the trying to remove the cooler air from the other end of the house to allow the warmer air to flow there more easily.
There are limits to how much intake pipe length can be used, But I suppose one could take a inline HVAC booster fan and put it inline say halfway between sections of pipe..
 
sure....maybe....but youd still be pulling possibly very low to negative pressure air, irregardless of which room it comes from, thru a smallish pipe, a great distance....creating more problems than its likely worth. Unless the house is a mobile home or really tight, id leave well enough alone. To check the home, just go ahead and run the stove for several house with all the doors and windows closed. Then walk over to the stove, stare at the fire, and let someone open a close-by window. Do you SEE a difference? Does the flame get bigger, or brighter? If so, try outside air. If no change, unless required by the manufacturer, its likely a waste of time.
 
GVA said:
I think he's talking about the trying to remove the cooler air from the other end of the house to allow the warmer air to flow there more easily.
There are limits to how much intake pipe length can be used, But I suppose one could take a inline HVAC booster fan and put it inline say halfway between sections of pipe..
Yep, that's what he's talking about, but it will only work if the closest leak to the outside air is near the stove and heated as it passes by, on it's way to the other end of the house. Otherwise, it will remove the cooler air from the other end of the house, only to replace it with even colder air from directly outside the house. Air that is removed has to be replaced by air from somewhere or you will create a vacuum (comes in from the outside through leaks in the building near the intake). The air being removed by the intake of the stove is going up the chimney (outside), not back into the house.
 
When I had the outside air intake still functional on my zero clearance fireplace, it was quite cold on the hearth when the unit wasn't on. I've read of putting a trap in the outside air line and that's supposed to get around this. I believe I've also seen a cable-operated shutoff damper somewhere...
 
Is this any good to use?

(broken link removed to http://www.woodlanddirect.com/Woodstove-Corner/Circulating-Fans/Air-Supply-Ventilator)
 
My vote is always fresh air from the outside.

Lots of products in a home competing for compustion air.

Straight out horizontal is the worst for allowing drafts from the out side.

When ever possible we install a "U" trap in the basement. Comes in from the out side ,drops down to the basement floor, then back up to the stove on the floor above us. We use all 26 gauge pipe mecaniclly connected (with screws no tape) so there is no violation of the fireratings between floor.

I have said before I am new to the hearth products trade and I am having a blast finding ways to improve this industry.


Look at the big picture of the home and combustion air and you start to realize how important it actually is
 
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